Effects of Si on the Microstructure and Work Hardening Behavior of Fe‒17Mn‒1.1C‒xSi High Manganese Steels

Renlong Xiong,Yi Liu,Haitao Si,Huabei Peng,Shanling Wang,Binhan Sun,Hanxin Chen,Hyoung Seop Kim,Yuhua Wen 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.10

In order to improve the work hardening capacity under low stresses and the yield strength of conventional Hadfield steels, theeffects of Si on the microstructure and work hardening behavior of the Fe‒17Mn‒1.1C‒xSi steels under both quasi-statictensile and low load impact are investigated. It is shown that the increase of the Si contents remarkably improves the yieldstrength by 36 MPa per 1 wt% Si in the investigated steel system without significant sacrifice of ductility. The decreasingeffect of Si on the stacking fault energy is strongly affected by carbon, although the variation of carbon content was small. This led to the unexpected similar stacking fault energy between 1Si and 2Si steel. With the increase of the Si contents forthe steels, the critical strain for the onset of mechanical twinning was lowered, which was controlled by the cooperationbetween the stacking fault energy and solid solution strengthening of Si. This resulted in the earlier initiation of mechanicaltwins and an increase in the twin volume fraction. Therefore, the work hardening capacities under both quasi-static tensileand low load impact tests were enhanced. It was also found that the impact deformation decreased as more mechanical twinsabsorbed the impact energy.

중국어 상성이 중국인의 한자어 발음에 미치는 영향 연구 : 부분이형동의어를 중심으로

Liu Si Yang,김영주 한국음성학회 2012 말소리와 음성과학 Vol.4 No.2

The purpose of this study is to find the influence of Chinese falling-rising tone on the pitch pattern of corresponding partly-different-form-same-meaning Sino-Korean words delivered by Chinese learners of Korean and to examine how the falling-rising tone of corresponding Chinese words affects the pitch patterns of Sino-Korean words. The scope of this research is limited to Chinese learners of Korean, especially on two groups of Sino-Korean words - AB:CB type and AB:AC type that the are second-most frequently occuring different-form-same-meaning Sino-Korean words. In this study, Chinese learners pronounced both Chinese words and corresponding Sino-Korean words. Learners’ pitch patterns were recorded and analyzed using software and compared with the tone of corresponding Chinese words. Experimental results showed that AB:CB type Sino-Korean words were not affected by Chinese 'falling-rising tone - high and level tone'. As well as AB:CB type, experimental results showed there were no significant influence on the pitch pattern of AB:AC type Sino-Korean words by Chinese falling-rising tone. But it was clear that Chinese learners' made pitch errors on both AB:CB type and AB:AC type Sino-Korean words. In conclusion, the Chinese learners' pitch patterns of partly-different-form-same-meaning Sino-Korean words are different from Korean native speakers', but their pitch errors cannot be attributed to Chinese falling-rising tone.

Transforming Growth Factor Beta-1 C-509T Polymorphism and Cancer Risk: A Meta-analysis of 55 Case-control Studies

Liu, Yang,Lin, Xian-Fan,Lin, Chun-Jing,Jin, Si-Si,Wu, Jin-Ming Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Aim: To investigate the association of transforming growth factor-beta 1 (TGF-${\beta}1$) C-509T polymorphism and susceptibility to cancer by means of meta-analysis. Methods: An extensive search was performed to identify eligible case-control studies investigating such a link. The strength of the association between TGF-${\beta}1$ C-509T polymorphism and cancer risk was assessed by pooled odds ratios (ORs) and 95%confidence intervals (95%CIs) in fixed or random effects models. Results: 55 published case-control studies with a total number of 21,639 cases and 28,460 controls were included. Overall, there was no association between TGF-${\beta}1$ C-509T and cancer risk in all genetic comparison models (TT vs. CC: OR=1.01, 95%CI=0.89-1.15; T vs. C: OR=1.01, 95%CI=0.94-1.07). However, a stratified analysis by cancer type indicated -509 T allele was significantly associated with decreased risk of colorectal cancer (CRC) (TT vs. CT/CC: OR=0.85, 95%CI=0.76-0.95), especially for Caucasians (TT vs. CT/CC: OR=0.83, 95%CI=0.71-0.98) and for population-based studies (TT vs. CT/CC: OR=0.78, 95%CI=0.68-0.89). Conclusion: This meta-analysis suggested that TGF-${\beta}1$ C-509T polymorphism might contribute to a decreased risk on colorectal cancer susceptibility, especially for Caucasians.

관광상품 라이브커머스 시청자 유입경로가 구매 및 구매의도에 미치는 영향: 시청몰입, 시청만족의 매개 효과

Liu Si-Yu,김진후 한국호텔외식관광경영학회 2024 호텔경영학연구 Vol.33 No.1

라이브커머스 시장이 급성장하는 가운데 관광상품 판매에도 라이브커머스가 이용되고 있지만, 그에 관한 연구는 부족한 실정이다. 본 연구는 관광상품 라이브커머스 방송 시청자를 대상으로 시청자 유입경로에 따라 상품의 구매 여부와 구매 의도가 달라지는지 알아보았다. 또, 시청유입경로와 구매 및 구매의도 간 관계가 어떤 과정을 거쳐 일어나는지 살펴보았다. 관광상품 라이브커머스 방송 시청경험이 있는중국인을 설문 조사해 얻은 자료를 분석해 다음 결과를 얻었다. 첫째, 로지스틱 회귀분석 결과 적극적 경로(예: 여행 관련 키워드 검색, 관심 키워드 또는 스트리머의 방송 알림설정 등)를 통해 유입된 시청자가 우연히 방송을 시청한 시청자보다 방송에서 판매하는 상품을 실제 구매하는 확률이 높았다. 둘째, 방송 중 실제구매하지 않은 사람을 대상으로 한 일련의 회귀분석 결과 적극적 경로로 유입된 시청자가 우연한 경로로유입된 시청자보다 방송에서 본 상품에 대해 더 높은 구매 의도를 갖고 있었다. 셋째, 유입경로와 구매의도간 관계에서 라이브커머스 방송에 대한 시청몰입과 만족이 매개역할을 하는 것으로 나타났다. 즉, 적극적경로로 유입된 시청자가 우연히 유입된 시청자보다 라이브커머스 방송에 더 몰입하고, 그러한 시청몰입상승이 직접, 그리고 시청만족 제고를 거쳐 간접적으로 구매의도 상승으로 이어짐을 확인했다. 이러한 결과는 라이브커머스 시청자 유입경로를 관리하고 시청몰입을 증가시킴으로써 판매 및 마케팅 효과를 증가시킬수 있음을 시사한다. Live-streaming commerce is growing and being used to sell tourism products, but research on it remains scarce. This study aims to determine whether tourism live stream viewers’ purchase and purchase intention differ by traffic sources (i.e., how they found the live stream they view). Furthermore, this study investigates the processes by which traffic source types lead to purchase and purchase intention. The data was obtained by surveying Chinese consumers who have viewed tourism live stream. The results of logistic regression indicated that active viewers (e.g., consumers who reached the live stream by searching for key words, by a notification that a streamer they follow is broadcasting, etc.) were more likely to purchase the products than passive viewers. Regression analysis for those who did not purchase the products showed that even if they did not purchase the products during the live stream, active viewers exhibited a higher purchase intention compared to passive viewers. The results from subsequent mediation analysis, using Hayes’ PROCESS macro, indicate that the flow and satisfaction of viewers mediate the relationship between traffic source and purchase intention. These findings suggest that tourism firms and marketers may enhance the marketing effects of live-streaming commerce by increasing active viewers and the level of flow within the content.

INTERACTIONS OF THE INFRARED BUBBLE N4 WITH ITS SURROUNDINGS

Liu, Hong-Li,Li, Jin-Zeng,Wu, Yuefang,Yuan, Jing-Hua,Liu, Tie,Dubner, G.,Paron, S.,Ortega, M. E.,Molinari, Sergio,Huang, Maohai,Zavagno, Annie,Samal, Manash R.,Huang, Ya-Fang,Zhang, Si-Ju American Astronomical Society 2016 The Astrophysical journal Vol.818 No.1

<P>The physical mechanisms that induce the transformation of a certain mass of gas in new stars are far from being well understood. Infrared bubbles associated with H II regions have been considered to be good samples for investigating triggered star formation. In this paper we report on the investigation of the dust properties of the infrared bubble N4 around the H II. region G11.898+0.747, analyzing its interaction with its surroundings and star formation histories therein, with the aim of determining the possibility of star formation triggered by the expansion of the bubble. Using Herschel PACS and SPIRE images with a wide wavelength coverage, we reveal the dust properties over the entire bubble. Meanwhile, we are able to identify six dust clumps surrounding the bubble, with a mean size of 0.50 pc, temperature of about 22 K, mean column density of 1.7 x 10(22) cm(-2), mean volume density of about 4.4 x 10(4) cm(-3), and a mean mass of 320M(circle dot). In addition, from PAH emission seen at 8 mu m, free-free emission detected at 20 cm, and a probability density function in special regions, we could identify clear signatures of the influence of the H II region on the surroundings. There are hints of star formation, though further investigation is required to demonstrate that N4 is the triggering source.</P>

The comparison of microbial communities in thyroid tissues from thyroid carcinoma patients

Liu Chen-Jian,Chen Si-Qian,Zhang Si-Yao,Wang Jia-Lun,Tang Xiao-Dan,Yang Kun-Xian,Li Xiao-Ran 한국미생물학회 2021 The journal of microbiology Vol.59 No.11

Thyroid carcinoma is a common endocrine organ cancer associated with abnormal hormone secretion, leading to the disorder of metabolism. The intestinal microbiota is vital to maintain digestive and immunologic homeostasis. The relevant information of the microbial community in the gut and thyroid, including composition, structure, and relationship, is unclear in thyroid carcinoma patients. A total of 93 samples from 25 patients were included in this study. The results showed that microbial communities existed in thyroid tissue; gut and thyroid had high abundance of facultative anaerobes from the Proteobacteria phyla. The microbial metabolism from the thyroid and gut may be affected by the thyroid carcinoma cells. The cooccurrence network showed that the margins of different thyroid tissues were unique areas with more competition; the stabilization of microcommunities from tissue and stool may be maintained by several clusters of species that may execute different vital metabolism processes dominantly that are attributed to the microenvironment of cancer.

Investigation on tolerance of Metarhizium flavoviride Ma130821 to environmental stress factors and responses on biological control of larvae of Potosia brevitarsis Lewis

Liu Si‐Yu,Lai You‐Peng,Du Guang‐Zu,Chen Bin 한국곤충학회 2022 Entomological Research Vol.52 No.11

Entomopathogenic fungi of Metarhizium spp., are one of the candidates for eco-friendly pest control instead of chemical control agents. But the development involved in producing a wide range of mycoinsecticides and application of biotechnology widely is restricted, usually due to the defect of slow action and sensitivity to environmental stresses. This study evaluates the tolerance of conidia of Metarhizium flavoviride Ma130821 to high temperature exposure, humidity level, ultraviolet radiation and the pathogenicity against larvae of Potosia brevitarsis Lewis under environmental stresses. Results showed that M. flavoviride Ma130821 had the higher tolerance ability to 40°C with continuous exposure for 24 h, the conidial germination rate was 54.00%, radial growth was 1.59 mm/day and sporulation was 9.37 × 106 conidia/cm2, the ability to desiccation with humidity of 53% (85.33%, 1.94 mm/d, 2.13 × 107 conidia/cm2), the ability of uvioresistant effect with 900 s radiation (98.11%, 0.91 mm/d, 8.87 × 106 conidia/cm2).Thedataofbioassayat artificial adverse condition had been fitted to the time–concentration–mortality (TCM) model. The cumulative mortality of P. brevitarsis larvae was 76.67% with conidial concentrations of 3.41 × 108 conidia/mL. The low lethal concentration (LC50) in 7 days after inoculation (DAI) and short lethal time (LT50) was 6.70 × 109 conidia/mL and 8.02 days, respectively. The mortality also reached to 73.33% at natural condition, with conidial concentration of 3.75 × 108 conidia/mL, but the LT50 delayed to 14.08 days. Our results demonstrate that entomopathogenic fungi M. flavoviride Ma130821, with significantly and superior antistress capacity and high virulence, could be considered a promising biocontrol agent against white grubs.

ST6Gal-I Predicts Postoperative Clinical Outcome for Patients with Localized Clear-cell Renal Cell Carcinoma

Liu, Hai-Ou,Wu, Qian,Liu, Wei-Si,Liu, Yi-Dong,Fu, Qiang,Zhang, Wei-Juan,Xu, Le,Xu, Jie-Jie Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Hyperactivated ${\alpha}2$-6-sialylation on N-glycans due to overexpression of the Golgi enzyme ${\beta}$-galactoside: ${\alpha}2$-6-sialyltransferase (ST6Gal-I) often correlates with cancer progression, metastasis, and poor prognosis. This study was aimed to determine the association between ST6Gal-I expression and the risk of recurrence and survival of patients with localized clear-cell renal cell carcinoma (ccRCC) following surgery. We retrospectively enrolled 391 patients (265 in training cohort and 126 in validation cohort) with localized ccRCC underwent nephrectomy at a single center. Tissue microarrays were constructed for immunostaining of ST6Gal-I. Prognostic value and clinical outcomes were evaluated. High ST6Gal-I expression was associated with Fuhrman grade (p<0.001 and p=0.016, respectively) and the University of California Los-Angeles Integrated Staging System (UISS) score (p=0.004 and p=0.017, respectively) in both cohorts. Patients with high ST6Gal-I expression had significantly worse overall survival (OS) (p<0.001 and p<0.001, respectively) and recurrence free survival (RFS) (p<0.001 and p=0.002, respectively) than those with low expression in both cohorts. On multivariate analysis, ST6Gal-I expression remained associated with OS and RFS even after adjusting for the UISS score. Stratified analysis suggested that the association is more pronounced among patients with low and intermediate-risk disease defined by the UISS score. High ST6Gal-I expression is a potential independent adverse predictor of survival and recurrence in ccRCC patients, and the prognostic value is most prominent in those with low and intermediate-risk disease defined by the UISS score.

Curved-quartic-function elements with end-springs in series for direct analysis of steel frames

Si-Wei Liu,Jake Lok Yan Chan,Rui Bai,Siu-Lai Chan 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.29 No.5

A robust element is essential for successful design of steel frames with Direct analysis (DA) method. To this end, an innovative and efficient curved-quartic-function (CQF) beam-column element using the fourth-order polynomial shape function with end-springs in series is proposed for practical applications of DA. The member initial imperfection is explicitly integrated into the element formulation, and, therefore, the <i>P</i>-<i>δ</i> effect can be directly captured in the analysis. The series of zero-length springs are placed at the element ends to model the effects of semi-rigid joints and material yielding. One-element-per-member model is adopted for design bringing considerable savings in computer expense. The incremental secant stiffness method allowing for large deflections is used to describe the kinematic motion. Finally, several problems are studied in this paper for examining and validating the accuracy of the present formulations. The proposed element is believed to make DA simpler to use than existing elements, which is essential for its successful and widespread adoption by engineers.

Multiple Sexual Partners as a Potential Independent Risk Factor for Cervical Cancer: a Meta-analysis of Epidemiological Studies

Liu, Zhi-Chang,Liu, Wei-Dong,Liu, Yan-Hui,Ye, Xiao-Hua,Chen, Si-Dong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

It's known that having multiple sexual partners is one of the risk factors of human papillomavirus (HPV) infection which is a major cause of cervical cancer. However, it is not clear whether the number of sexual partners is an independent risk factor for cervical cancer. We identified relevant studies by searching the databases of MEDLINE, PubMed and ScienceDirect published in English from January 1980 to January 2014. We analyzed those studies by combining the study-specific odds ratios (ORs) using random-effects models. Forty-one studies were included in this meta-analysis. We observed that the number of sexual partners was associated with the occurrence of non-malignant cervical disease (OR=1.82, 95%CI 1.63-2.00) and invasive cervical carcinoma (OR=1.77, 95%CI 1.50-2.05). Subgroup analyses revealed that the association remained significant after controlling for HPV infection (OR=1.52, 95%CI 1.21-1.83 for non-malignant disease; OR=1.53, 95%CI 1.30-1.76 for invasive cervical carcinoma). We found that there was a non-linear relation of the number of sexual partners with both non-malignant cervical disease and invasive cervical carcinoma. The risk of both malignant and non-malignant disease is relatively stable in women with more than 4-7 sexual partners. Furthermore, the frequency-risk of disease remained significant after controlling for HPV infection.The study suggested that h aving multiple sexual partners, with or without HPV infection, is a potential risk factor of cervical cancer.